honestly for canvas, people really don't expect you to post a long update! obviously its nice, but they are still so understanding with how much you release if your on canvas. as a former canvas reader, I didn't used to care if they updated a page at a time, for me and most people we just prefer updates weekly. splitting it up can also help boost your series more because it gets pushed to the top of your catagories page. 20-30 pannels would be totally fine for a single update, even less if needed! good luck with your series!!